Use of Finite Element Analysis and Fatigue Failure Model to Estimate Costs of Pavement Damage Caused by Heavy Vehicles

Abstract

The transportation of heavy loads potentially causes more damage to pavements than regular vehicle traffic. This study investigated the impact of heavy vehicles on asphalt pavement to optimize axle configurations, select routes, and estimate permit costs. Finite element analysis, validated by field measurement, was used to evaluate pavement responses under various heavy load scenarios. From the results, the remaining pavement service life was predicted with the use of pavement distress models. The permit cost for a single pass of a heavy vehicle was estimated from the reduction of pavement fatigue life and associated pavement maintenance cost. Sensitivity analyses were conducted to determine factors affecting pavement fatigue damage and permit costs. Field measurement indicated that a significant longitudinal pavement defection occurred under the heavy vehicle. The results from finite element analysis showed a significant overlapping effect between multiple axles over the depth. Pavement defection was caused mainly by the deformation within subgrade soil. Generally, pavements with high thickness and stiffness would incur less damage and lower permit cost. A pavement structure with deep bedrock would incur more damage and higher cost. Because of the temperature dependency of asphalt mixtures, the damage cost in winter was much less than that in summer, even considering the potential weak subgrade during the spring thaw. It was also found that newly constructed pavements would incur higher permit cost than relatively older pavements. To reduce potential pavement damage and the associated cost effectively, the number of dollies and axle distance should be increased to spread the load to a larger area.